AUTOIMMUNE DISORDERS


DEFINITION

Autoimmune disorders are conditions in which a person's immune system (the network of organs, tissues, cells, and chemicals whose job it is to protect the body from foreign invaders, like bacteria and viruses) attacks the body's own cells. As cells are killed, tissues begin to die off.

DESCRIPTION

Many forms of autoimmune disorders are now recognized. These disorders are classified as general or organ specific. A general autoimmune disorder is one that attacks a number of tissues throughout the body. An organ specific disorder attacks only one type of organ at a time.

Some examples of autoimmune disorders include:

  • Systemic lupus erythematosus (pronounced LOO-puhs er-uh-THEM-uhtuhs; see lupus entry) is a general autoimmune disorder. The condition occurs primarily in young and middle-aged women.
  • Rheumatoid (pronounced ROO-muh-toid) arthritis (see arthritis entry) is inflammation of joints. It occurs when the immune system attacks and destroys tissue that lines the bone joints and cartilage.
  • Goodpasture's syndrome is an inflammation of the lungs and kidneys. It occurs primarily in young males.
  • Grave's disease affects the thyroid gland. The diseases causes the gland to make an excessive amount of thyroid hormone.
  • Hashimoto's thyroiditis also affects the thyroid gland. But it causes a reduction in the amount of thyroid hormone produced by the gland.
  • Pemphigus vulgaris (pronounced PEM-fi-guhs vuhl-GARE-uhs) is a group of autoimmune disorders that affects the skin.
  • Myasthenia (pronounced MY-uhs-THEE-nee-uh) gravis is caused when messages from nerve cells to muscles are disrupted. Muscles become weakened.
  • Scleroderma (pronounced SKLEER-uh-DIR-muh) causes a toughening and hardening of connective tissue.
  • Autoimmune hemolytic anemia is a condition that causes damage to red blood cells (see anemia entry).
  • Autoimmune thrombocytopenic purpura (pronounced THROM-buh-SI-tuh-PEE-nick PIR-puh-ruh) results in destruction to blood platelets, cells that help blood to clot.
  • Pernicious anemia develops when the body can no longer make use of vitamin B12, resulting in a decreased production of red blood cells (see anemia entry).
  • Sjögren's (pronounced SHO-grenz) syndrome occurs when glands are damaged, increasing the loss of water by the body and causing excessive dryness.
  • Ankylosing spondylitis (pronounced ANG-kuh-lozing spon-duh-LIE-tis) results in the destruction of joints and soft tissue in the spine.
  • Vasculitis is a group of disorders in which blood vessels are destroyed.
  • Type I diabetes mellitus (see diabetes mellitus entry) is caused when the islet cells of the pancreas are damaged, preventing the release of insulin to the body.

CAUSES

Autoimmune disorders occur when the body's immune system becomes confused. Because the immune system is used to fight foreign invaders, under normal circumstances, the immune system is able to tell if a group of cells is part of the body or not. For example, it generally has no problem recognizing that bacteria and viruses do not belong to the body. In such cases, the immune system takes a number of actions to fight off and kill the foreign cells.

Autoimmune Disorders: Words to Know

Anemia:
A medical condition caused by a reduced number of red blood cells, characterized by general weakness, paleness, irregular heart beat, and fatigue.
Antibody:
A chemical made by the immune system to destroy foreign invaders.
General autoimmune disorder:
An autoimmune disorder that involves a number of tissues throughout the body.
Immune system:
A network of organs, tissues, cells, and chemicals designed to fight off foreign invaders, such as bacteria and viruses.
Organ specific disorder:
An autoimmune disorder in which only one type of organ is affected.
Steroids:
A group of naturally occurring substances that are very effective in reducing pain and swelling in tissues.

An important component of the immune system is the production of antibodies. Antibodies are chemicals made by the immune system to destroy foreign invaders. Antibodies are very specific. The immune system makes only one type of antibody for each different foreign invader. For example, there is a very specific antibody for each different virus that gets into the body.

But the immune system sometimes makes mistakes. It may somehow regard cells from its own body as being foreign. In such cases, it takes the same actions against those cells as it does against bacteria, viruses, and other truly foreign organisms. It actually begins to destroy healthy, normal cells in the body. When this happens, an autoimmune disorder results.

ORGAN TRANSPLANTATION

An organ transplantation may be necessary when a person's heart, kidney, lungs, liver, or some other vital organ becomes diseased. In such cases, a second person may offer to donate his or her organ to replace the diseased or damaged organ. Autoimmune disorders can often occur when organs are transplanted from one person to another. The problem is that the patient's immune system may reject the donated organ because it thinks the donated organ is a foreign body. It begins to attack the new organ as it would bacteria, viruses, fungi, or other disease-causing organisms.

Patients who receive transplanted organs are also given immunosuppressant drugs. An immunosuppressant drug is a chemical that reduces the body's natural defenses against foreign bodies. It gives the donated organ a chance to become implanted in the new body and start functioning again.

However, immunosuppressant drugs can cause a different set of problems: they prevent the immune system from doing its normal jobs; a patient becomes much more sensitive to diseases that the immune system is usually able to fight; and patients may become ill very easily. For most patients, though, the tradeoff is well worth it. Without the new, healthy organ and the immunosuppressant drugs to sustain it, they might not live.

SYMPTOMS

Each type of autoimmune disorder has its characteristic symptoms. Some of these symptoms include:

  • Systemic lupus erythematosus: Fever, chills, fatigue, weight loss, skin rashes, patchy hair loss, sores in the mouth or nose, problems with the digestive system, vision problems and, in women, irregular periods. Lupus can also affect the central nervous system, causing seizures, depression, and mental disorders.
  • Rheumatoid arthritis: Mild fever, loss of appetite, weight loss, and, most important, pain in the joints. In advanced stages, rheumatoid arthritis can lead to deformities of the body.
  • Goodpasture's syndrome: Fatigue and paleness. Bleeding may occur in the lungs or the urinary system.
  • Grave's disease: An enlarged thyroid gland, weight loss, sweating, irregular heart beat, nervousness, and an inability to tolerate heat.
  • Hashimoto's thyroiditis: Generally no symptoms.
  • Pemphigus vulgaris: Blisters and deep, open sores on the skin.
  • Myasthenia gravis: General muscle weakness that may develop into paralysis. Chewing, swallowing, and breathing may be difficult.
  • Scleroderma: Pain, swelling, and stiffness of the joints. The skin takes on a tight, shiny appearance. Digestive problems may develop, leading to weight loss, loss of appetite, diarrhea, constipation, and swelling of the abdomen.
  • Autoimmune hemolytic anemia: Fatigue and tenderness in the abdomen.
  • Autoimmune thrombocytopenic purpura: Tiny, red dots on the skin, unexplained bruises, bleeding from the nose and gums, and blood in the stool.

A view of the retina showing symptoms of lupus erythmatosis, a type of autoimmune disorder. (© 1997 SPL, Sue Ford/Science Photo Library. Reproduced by permission of Custom Medical Stock Photo.)
A view of the retina showing symptoms of lupus erythmatosis, a type of autoimmune disorder. (© 1997
SPL, Sue Ford/Science Photo Library
. Reproduced by permission of
Custom Medical Stock Photo
.)

  • Pernicious anemia: General weakness, sore tongue, bleeding gums, and tingling in the arms and legs. A deficiency of vitamin B12 can also cause a number of nervous disorders, including weakness, lack of coordination, blurred vision, loss of the sense of taste, ringing in the ears, and loss of bladder control.
  • Sjögren's syndrome: Excessive dryness of the mouth and eyes.
  • Ankylosing spondylitis: Lower back pain that usually moves up the spine.
  • Vasculitis: Symptoms range widely depending on the part of the body affected.
  • Type I diabetes mellitus: Fatigue and an abnormally high level of sugar in the blood.

DIAGNOSIS

The first step in diagnosing any autoimmune disorder is usually a review of symptoms. An additional step involves ruling out other medical conditions that might produce similar symptoms.

The final diagnosis for an autoimmune disorder, however, usually involves a blood test. The purpose of the blood test is to look for antibodies. If ankylosing spondylitis is present in the body, for example, very specific antibodies for that disorder will be present. If no such antibodies are found in the patient's blood, the disorder is not present.

TREATMENT

Treatments differ for each type of autoimmune disorder. However, there is one treatment that is common to many forms of autoimmune disorders. That treatment is the use of drugs to reduce the inflammation, swelling, and pain that accompanies most autoimmune disorders. Inflammation occurs when antibodies attack and irritate tissues. Some common drugs, such as aspirin and ibuprofen (pronounced i-byoo-PRO-fuhn), help reduce inflammation and pain. Aspirin should not be given to children due to the danger of contracting Reye's syndrome (see Reye's syndrome entry). A more powerful medication is one of the many steroid medications. But steroids have some serious long-term side effects, and they are generally used only in severe cases or in situations where milder drugs are ineffective.

PROGNOSIS

Prognosis differs for each type of autoimmune disorder.

PREVENTION

There is currently no way to prevent any of the autoimmune disorders.

See also: Anemias, arthritis, diabetes, and lupus.

FOR MORE INFORMATION

Books

Aaseng, Nathan. Autoimmune Diseases. New York: Franklin Watts, 1995.

Organizations

American Autoimmune Related Diseases Association, Inc. 15475 Gratiot Avenue, Detroit, MI 48205. (313) 371–8600. http://www.aarda.org.